The invention concerns a pressure regulating inlet-and-outlet valve for a space or vessel enclosed by a wall or barrier and sealed off from the outside.
Such pressure regulating inlet-and-outlet valves are well known in the art. Spring-loaded check valves, for example, are used to limit the pressure in sealed spaces in a housing or vessel.
The conventional ball-and-spring check valves have a number of drawbacks. They require several parts that move in relation to one another with narrow tolerances within a valve housing. Furthermore, both over and under pressure cannot be compensated with one and the same valve. These valves react relatively inertly to differences in pressure, and it is impossible to provide for a constant pressure within narrow limits.